How much does you pp vary while towing someone?

[r3612]

I think my pp is havin some trouble keeping the speed. Seems like it's surging a little compared to my old88 2001 nauty's. I adjusted the kdw and nn. If i recall correctly the nn is at 165 and the kdw is at 245. Not 100% on the kdw though could be way off. It seems to vary all the way to 1mph on the digital readout while someone is back there. Is this normal for a v-drive cause my old nauty's stood solid it seemed. What value's do you guys have set? I have a Centurion hurricane with the merc 350 mpi and run about a total of 1200lbs. (500 in the bow and the factory 3 tanks)


Thanks
Kris

[X-Star]

I have my kdw set to 50. If you read the manual, i believe 50 is the default. I tried playing with it a little a long time ago by turning it up, but it started doing what you said so I put it back to 50. Woks good.

[K-dub]

mines at the default, too. I never vary more than .5 mph...

[Xbrdr1]

From PP People.....
NN works like this:
Say you set it at 160, that means the system is measuring the time for
the last 160 paddlewheel turns and calculating the speed based on the
last 160 turns. When it sees the 161 turn it eliminates the 1st turn so
it is always using the last 160 turns. So when a change in speed
happens it takes a little while for the average of the 160 pulses to
decrease. Hence the higher you set NN the longer it will take for the
speed reading (average of all the pulses) to either increase or
decrease. The lower NN is set the quicker you will see a change in
speed reflected on your display. But if NN is to low say 60 and the
paddlewheel gets a disturbance for say 40 pulses then all of sudden the
system might think you have dramatically changed speed and make a huge
compensation when in fact the speed of the boat didn't really change.
But if you had the NN set to 200 it would average the 40 bad pulses in
with 160 correct ones and the system would ride out the bad pulses much
smoother.

[Xbrdr1]

Kdw
This is a bit harder to explain in a technically manner unless you are
familiar with electronic control systems. But it's easy to understand
in the real world. It's basically how aggressively the system will
react to changes in speed.

For example if you had a high KdW say 200 and the boat slowed by .5 mph,
the system would then apply additional throttle to compensate for the
change and regain the boat speed within lets say 1 second. If you had a
setting of 100 it may take 2 seconds. But the catch to this one is that
if it's to high it will not only compensate for the .5 mph it may shoot
the speed up to .3 mph over the set speed then .1 mph under then finally
to the correct speed, which will cause the boat to surge.

In Conclusion:
Now if you consider how these two values interact you'll see it can be
quite complex. If your NN is low and KdW is high, you might notice the
boat constantly adjust itself for no particular reason. If NN is high
and KdW is low the system will be much slower to react to changes in
speed and by the time it reacts there is already another change so it's
constantly chasing itself. It's usually best to adjust NN until you see
a nice steady speed on your digital speedo, with reason. And then tweak
the KdW for optimum performance.